The Normal Monster "Harpie Lady" and its first four Effect Monster retrains ("Cyber Harpie Lady", "Harpie Lady 1", "Harpie Lady 2", and "Harpie Lady 3") are considered as the same card when constructing a Deck: a player cannot use three copies of the original "Harpie Lady" and three of "Cyber Harpie Lady"
This allows Firewall to summon the Dark World monster from hand, allowing Grapha to re-use its effect and create an infinite damage loop
Still behaving
For example, Jhovall Queen reads "Attacking doesn't cause Jhovall Queen to tap", but officially it just has vigilance instead
Dragon World: A good card
Their WIND monsters are based on the Shu, the WATER monsters are based on the Wu, the FIRE monsters were based off of the Wei, and the DARK monsters are based on figures from Dong Zhuos faction, which was independent from the other kingdoms